Which oxygen delivery device uses a flow of 10-15 L/min and provides FiO2 of 60%-100%, with the bag kept from collapsing during inspiration?

Which oxygen delivery device uses a flow of 10-15 L/min and provides FiO2 of 60%-100%, with the bag kept from collapsing during inspiration?

• A. Nonrebreather mask delivering 10-15 L/min and FiO2 60%-100%
• B. Nasal cannula up to 6 L/min
• C. Partial rebreathing mask 8-15 L/min
• D. Simple face mask 6-10 L/min

Answer: (A)

The device that fits this scenario is the nonrebreather mask, which provides a very high concentration of oxygen by using a reservoir bag and one-way valves. When you set a flow of 10–15 L/min, oxygen continuously fills the reservoir bag. The one-way valves prevent exhaled air from entering the bag, so the inhaled breath draws mostly fresh oxygen from the bag. Because the bag remains inflated, the patient can inhale close to 100% oxygen on each breath, typically achieving an FiO2 in the range of about 60–100% with proper fit and adequate flow. If the bag were to collapse during inspiration, room air could be drawn in, diluting the oxygen concentration and reducing FiO2. Nasal cannulas deliver oxygen through tubing into the nostrils and max out around 6 L/min, with FiO2 generally up to about 44%, and they have no reservoir bag. Partial rebreather masks do provide a reservoir and can reach relatively high FiO2, but the exact FiO2 is more variable and usually not as high or as reliably maintained as with a true nonrebreather mask. Simple face masks deliver oxygen without a reservoir and typically provide roughly 40–60% FiO2 at about 6–10 L/min, not reaching the highest concentrations.

The device that fits this scenario is the nonrebreather mask, which provides a very high concentration of oxygen by using a reservoir bag and one-way valves. When you set a flow of 10–15 L/min, oxygen continuously fills the reservoir bag. The one-way valves prevent exhaled air from entering the bag, so the inhaled breath draws mostly fresh oxygen from the bag. Because the bag remains inflated, the patient can inhale close to 100% oxygen on each breath, typically achieving an FiO2 in the range of about 60–100% with proper fit and adequate flow. If the bag were to collapse during inspiration, room air could be drawn in, diluting the oxygen concentration and reducing FiO2.

Nasal cannulas deliver oxygen through tubing into the nostrils and max out around 6 L/min, with FiO2 generally up to about 44%, and they have no reservoir bag. Partial rebreather masks do provide a reservoir and can reach relatively high FiO2, but the exact FiO2 is more variable and usually not as high or as reliably maintained as with a true nonrebreather mask. Simple face masks deliver oxygen without a reservoir and typically provide roughly 40–60% FiO2 at about 6–10 L/min, not reaching the highest concentrations.